Steam-boiler



(No Model.) 2 Sheets-Sheet; 1.

M. H. PLUNKBTT.

Y s-TEAMBOILER. y No. 522,271. Patented July 3, 1894,.

.Z W'xcneeees z hwento r (No Model.) 2 Sheets-Sheet; 2.

M. H. PLUNKETT. STEAM BOILER.V

l1\I0.5z2,.2'11. v Patented July s.. 1894l UNITE-D' :STATS PATENT (DF-FICE. l

MICHAEL H. vPLUNKETT, OF BALTIMORE, MARYLAND.

SPECIFICATION fcrlilng' part Of Letters Patent N0. 522,271, dated July 3, 1824.

Application filed J' uly 20, 1893i Serial No. 481,015. (No model.) A

To all whom it may concern/.-

Be it known that I, MICHAEL 1I. PLUNKETT, a citizen of the United States, residingr at Baltimore city` in the State of Maryland, have invented certain new and useful v.Improvements in Steam-Boilers; and I do declare the following to be a full, clear, and exact description of the invention,such as will enable others skilled in the art -to which it appertains to make and use the same, reference being had to the accompanying drawings, and tothe Iigures of reference marked thereon, which form a part of this specification. v

My invention relates to boilers of the class known as water tube boilers and has forI its object to furnish a boiler of this. class which shall be light in weight, occupy but little floor space, rapidly generate and safely carry a very high working pressure of steam, be cheap in construction and have all its partsl readily accessible forV purposes of lcleaning. and repair, and which may be taken apart in sections and lowered down the fire room hatch Without cutting the decks.

With Athis objectin view my invention consists in the improved' construction, arrangement and combination of parts hereinafter fully described, and afterward specifically pointed out in the subjoined claims.

In the accompanying drawings, Figure 1 is a central, vertical section through a boiler constructed in accordance with my invention.A

Fig. 2 is a view partly in plan with parts of the boiler removed and partly in section, showing in plan the central steam and water chamber and fur of the surrounding cylindrical steam chambers with their man hole covers removed,and in section part of the tubular water wall and one of the cylindrical steam chambers. Fig. 3 is a view in elevation of one of thetubes of the tubular water wall. Fig. 4 is a sectional detail view showingthe manner of connecting the tubes of the water wall with a horizontal, annular circulating pipe or chamber and Fig. 5 is a view Ain elevation of partiof the annular circulating base chamber or pipeand parts of twog of the tubes of `the vertical water wall, the hand hole cover being removed.

Like numerals of reference mark the same parts wherever they occur in the various figures of the drawings. -f

Referring to the drawings by numerals 1 is the base of the boiler Aupon which is-y suitably su pportedy a jacket 2 which may be lined or stuffed with asbestus, or otherwise constructed with a view to the prevention of radiation of heat and in land boilers may be built of brick. Upon the base 1 is supported acentral cylinder y3 which surrounds a central water chamber 4 and extends the whole length of 'the boiler,its upper portion forming a central steam chamber 5 covered by a crown 6 having aman hole 7 with a suitable guard S. Forked end braces 9 within the cyl- `inder 3 connect the crown 6 with the base 1.

Within the cylinder 3.is a ,smaller cylinder "|10 open at its top and bottom and lsupported at the top by braces 1l 'secured to'the inside A'of cylinder 3. Centrally disposed inside of Vthese cylinders is the `feed water pipe 12 which discharges near the top of vthe water chamber 3 and'has at its upper end downvward turned nozzles 13 to give direction to the currents.

The fire chamber surrounds the water cylinder and has segmentally arranged grate bars 14 suitably supported in place'with any suitable door or opening for the introduction of fuel.v v 'f Surrounding the central steam 'chamber 5 are cylindrical steam chambers 15 connected near their bottoms to the central chamber by radially disposed pipes 16 and near their,l tops Vby smaller radially disposed pipes 137. These chambersmay also be connected to `each other by means of pipes 18 as shown in Figs. 1 and 2 and are connected with the central water chamber 4 by curved pipes 19 which at their lower horizontal ends pierce the cylinder 3, while at their upper vertical ends they pierce the bottom of the steam chambers 15 and are so arranged that they are brought to the bottom of the steam chambers 15 in concentric circular series. Those of'these curved pipes nearest the central water chamber 4 (marked 20) have, within each of them a similarly curved pipe 21 of smaller diameter, which'at its top extends a short distance into the steam IOO 2, forming a tubular water wall tothe tire box or combustion chamber. These tubes are connected at their lower ends to a horizontally arranged annular pipe or chamber 2i of greater diametric capacity than the tubes. At their upper ends the tubes 22 are connected to a similar horizontal pipe 25 while the tubes 23 'enter the bottoms of the steam chambers 15 through the pipe 25, this pipe being bent at these points on the circle" of the walls of the steam chambers 15 and entering into these chambers around their outer edges.

The boiler is surmounted by a funnel and smoke stack 26 forming an extension of the re box or combustion chamber 27.

In `constructing my boiler I expand the ends of all steam tubes into place, obviating the use of screw joints in the fire which are very objectionable. The pipes connecting the steam chamber are secured in the same way, asare all the tubes except the lower ends of thereturn pipes outside the boiler. Each ofthe tubes of the water Wall is plugged at each end by a washer-like bored plate or plug 28 having a central opening 29 (this may beaccomplished by reducing the diameter of the tubes at the ends). This plug is Hush with theiend of the tube by which construction the vertical tube can `easily be `put in` 24. A thimble 31 is now placed in position through the holes in the plug 28 and cham-` ber 24, and its ends expanded by any suitablemeans, access to theinterior of chambersA Maud-25 being had through suitable hand holes 32 closed by a guard 33. The openings` 30 in the chambers 24 and 25 being some-;y

`what smaller in diameter than the tubes 22l and `23there is sufficient metal left between them to allow them to be arranged closel against eachother, without weakening the@ structure, thus forming a complete and con-1@ tinuous tubular water wall of great strengthj Return tubes 3a extend from the outery sides of the steam drums or cylinders 15, downward, outside the jacket, down to the` bottom of the boiler, and at their lower ends aref connected to the central water chamber by radially converging tubes 35, these radial, tubes, at their joints with the return tubes, being connected with the annular chamber 22by means of vertical tubes 3G. All of the" steam drums or chambers are provided with` separatingplates 37, to prevent the water fol# lowing the steam.

It will be observed that the lower circularl chamber 24 is located above the door or open-i` ing of the fire box, thus obviating the neces-i|` sity of joints or arching that chamber to pre-i ventit from'interfering with the fuel opening.i

The operation of my improved boiler is as follows: Water being supplied through the feed water pipe, and the boiler being fired up the cylinder ofthe central Water chamber, the curved tubes 19 and the tubular water wall are all quickly heated and their contained water rapidly generated into `steam which `passes upward, creating a `rapid i circulation through the tubes into the steam :chambers 15. All these chambers being connected with each other, an even pressure always exists in each, and each of them being relatively so much smallerthan the steam chamber would beit' the `Whole of the upper part of theboiler were a single steam chamber they canbe made of very much lighter iron or steel than would be necessary in such a structure,.alsogiving a larger steam room, a larger` separating surface and a greater amount of `heating surface than any ordinaryconstruction. Thesteam moving upward in the pipes 19 will naturally `carry some water with itand as soon asthis water reaches the top ofthe inside `bent tube 21, a downward watercurrent will immediately begin to flow through that tube, the `water being returned `tothe insidefof the inner cylinder 10 of the water chamber. This cylinder being removed from contact Awith the Iire, will be cooler than cylinder 3i and as a consequence a continuonscirculation, ,(being a downward current inside of the cylinder 10 and an upward current between it and the cylinder 3) will be kept up. Water will also be returned to the water chamber through pipes 16 and return `tubes 34:.

The applicationof the heat tothe generating surfaces is direct and economical, such surfaces absorbing the greatest amount of heat and the water being divided into a large number of circulating currents steam is quickly generated in great quantity with the least possible ebullition or disturbance of the water and a greatly decreased consumption offuel.

Having thusfully described my invention, what I claim as new, and desire to secure by Letters Patent ofthe United States, is

1. A steam boiler provided with ah series of cylindrical steamchambers grouped about a `central steam and water chamber and bent tubes connecting the sides of the central cham- 1 ber with the bottom of the cylinders, substantially asset forth.

2. A steam boiler provided witha central water and steam' chamber, a series of cylindrical steam chambers grouped about the central chamber, connecting tubesbetween the IOO IIO

central chamber and the sides of the group of cylindrical chambers and direct yconnections between the several chambers of the group, as set forth.

3. A steam boiler having a central steam and water chamber, a directly connected series of smaller chambers grouped about and directly connected to the central chamber and curved pipes connecting the series of chambers with the central chamber, as set forth.

4. In a steam boiler, a water wall consisting of vertical tubes and horizontal annular chambers, the ends of said Vertical tubes resting against the surface of the horizontal chambersand being plugged with plates perforated to register with perforations in the annular chambers, and expanded thimbles in said registering perforations, as set forth.

5. The steam boiler herein described consisting of the central water chamber, the series of cylindrical steam chambers grouped about it, the curved tubes connecting them, v

the horizontal annular chambers, the Water wall 'tubes connecting them and the series of steam chambers, the return tubes leading down from the series of chambers outside the boiler, the radial tubes connecting them with the central chamber, and the vertical tubes connecting them with the lower horizontal annular chamber, as set forth. n

6. A steam boiler having a series of steam chambers grouped about a central water and steam chamber, an upper and a lower annular chamber, and a water wall of closely placed tubes connecting the two annular chambers, part of these water wall tubes being arranged at their upper ends in the arcs kof the circumferences of the chambers of the group and openinginto said chambers, as set forth.

In testimony whereof I affix my signature in presence of two witnesses.

MICHAEL H. PLUNKETT. Witnesses:

AUGUSTUS ALBERT, HY. A. ALBERT. 

